The evolving impact of microfabrication and nanotechnology on stent design

Noncoronary atherosclerotic vascular disease, including symptomatic lower extremity peripheral arterial disease (PAD), promises to extract a steadily rising medical and economic toll over the coming decades. Although drug-eluting stents have led to substantial advances in the management of coronary atherosclerosis, endovascular treatment of noncoronary, peripheral arterial lesions continues to yield high restenosis rates and early clinical failures. In this report, we review recent developments in microfabrication and nanotechnology strategies that offer new opportunities for improving stent-based technology for the treatment of more extensive and complex lesions. In this regard, stents with microfabricated reservoirs for controlled temporal and spatial drug release have already been successfully applied to coronary lesions. Microfabricated needles to pierce lesions and deliver therapeutics deep within the vascular wall represent an additional microscale approach. At the nanoscale, investigators have primarily sought to alter the strut surface texture or coat the stent to enhance inductive or conductive schemes for endothelialization and host artery integration. Nanotechnology research that identifies promising strategies to limit restenosis through targeted drug delivery after angioplasty and stenting is also reviewed.